A main shaft constant speed driving floating swash plate type axial conical cylinder block plunger pump

Abstract

The application relates to the technical field of pumps and discloses a main shaft constant-speed driving floating swash plate type axial conical cylinder body plunger pump, which comprises a pump body and a main shaft installed in the pump body, the main shaft is connected with an external prime mover, a swash plate, a rotary disc and a cylinder body are sequentially arranged on the main shaft from the front end of the pump body to the rear end of the pump body, the swash plate is connected with the inner cavity of the pump body, the rotary disc is matched with the swash plate and is connected with a plurality of plungers in the cylinder body; a hinged structure is arranged on the main shaft, the rotary disc is connected with the main shaft through the hinged structure, the rotary disc is configured to be converted from spherical surface contact to linear contact through the hinged structure, axial movement can be generated between the rotary disc and the hinged structure when the main shaft rotates; the plungers in the cylinder body are arranged to be inclined along the axis of the main shaft. The application eliminates the restriction on the relative axial movement of the spherical hinge and the rotary disc, improves the contact stress intensity of the hinged structure, reduces the pv value of the flow distribution pair relative to the cylindrical cylinder body structure, improves the oil suction capacity, and enables the pump to reach a higher rotating speed.

Description

Technical Field

[0001] This invention relates to the field of piston pump technology, and in particular to a main shaft constant speed driven floating swashplate axial conical cylinder piston pump. Background Technology

[0002] Hydraulic transmission technology plays a crucial role in modern industry, especially in the construction machinery sector, where most construction machinery relies on it. The hydraulic pump, as a core component of the hydraulic system, is a key power source, and the swashplate axial piston pump is a common type of pump in construction machinery hydraulic systems due to its wide application.

[0003] With the pursuit of dual carbon goals—reducing carbon emissions and achieving carbon neutrality—fluid power technology faces new opportunities and challenges. Dual carbon policies are driving the construction machinery industry's transformation from traditional internal combustion engines to electric new energy sources. This transformation places new technological demands on swashplate axial piston pumps in hydraulic systems, posing a challenge to technological innovation for traditional pump types. To address the challenges and demands of this new technology, the inventors previously proposed a series of novel floating swashplate axial piston pump architectures. However, the existing floating swashplate axial piston pump architectures, especially the ball-cage type ball joint-ball bearing transmission scheme, still have the following shortcomings: 1. Firstly, during the synchronous driving of the rotary table by the spindle, since the balls are always at the intersection of the double arc surfaces, i.e., the center of the ball is on the angle bisector, the rotary table is in spherical contact with the ball joint and the cage, thus restricting the axial movement of the ball joint and the rotary table; 2. The previously proposed inner and outer raceways are both single circular arc raceways, resulting in low installation tolerance and difficulty in controlling the contact angle, which varies with the initial clearance and load, thus limiting the strength against contact stress; 3. Under high-speed conditions, the oil suction capacity of the cylindrical block axial piston pump is weak, especially in large displacement pumps where the diameter of the distributor plate is also relatively large, leading to reduced oil suction capacity and a relatively high PV value of the distributor pair, which limits the increase in the speed of the axial piston pump.

[0004] Therefore, this patent further proposes a main shaft constant speed driven floating swashplate axial conical cylinder plunger pump to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to provide a main shaft constant speed driven floating swashplate axial conical cylinder plunger pump to solve the problems existing in the prior art.

[0006] To achieve the above objectives, the present invention provides the following solution: The present invention provides a main shaft constant speed driven floating swashplate axial conical cylinder plunger pump, comprising: a pump body and a main shaft installed in the pump body, wherein the main shaft is connected to an external prime mover;

[0007] The main shaft is provided with a swashplate, a rotary table and a cylinder in sequence from the front end of the pump body to the rear end of the pump body. The swashplate is connected to the inner cavity of the pump body, and the rotary table is adapted to the swashplate and connected to a number of plungers in the cylinder body.

[0008] A hinge structure is provided on the main shaft, the rotary disk is connected to the main shaft through the hinge structure, and is configured such that the rotary disk changes from spherical contact to linear contact through the hinge structure, and axial movement can occur between the rotary disk and the hinge structure when the main shaft rotates;

[0009] The plunger inside the cylinder is inclined along the axis of the main shaft.

[0010] According to the present invention, a constant velocity driven floating swashplate axial conical cylinder plunger pump with a main shaft includes a hinge structure comprising:

[0011] A ball joint is provided on the main shaft;

[0012] A retainer is fitted onto the ball joint, and the rotary table is hinged to the ball joint via the retainer;

[0013] A number of balls are rotatably connected to the cage at equal intervals along the circumference, and the outer wall of the ball joint and the inner wall of the rotary table are respectively in contact with the balls.

[0014] According to the present invention, a main shaft constant speed driven floating swashplate axial conical cylinder plunger pump is provided, wherein the cage is provided with a plurality of through holes at equal intervals along the circumference, the outer wall of the ball joint is provided with a plurality of inner raceways at equal intervals along the circumference, and the inner wall of the rotary disk is provided with a plurality of outer raceways at equal intervals along the circumference. The plurality of inner raceways and the plurality of outer raceways correspond one-to-one with the plurality of through holes, and the plurality of balls are respectively installed in the plurality of through holes and roll in the inner raceways and the outer raceways.

[0015] According to the present invention, a main shaft constant speed driven floating swashplate axial conical cylinder plunger pump is provided, wherein the through hole is a waist-shaped through hole, and the cross-section of the inner raceway and the outer raceway is one of a single circular arc, an ellipse or a double circular arc.

[0016] According to the present invention, a constant speed driven floating swashplate axial conical cylinder plunger pump has the outer spherical center of the cage being B, the inner spherical center of the cage being C, and the coincidence point of the center of the circle forming the plane of the swashplate swing center, the center of the cage, and the center of the plunger ball being O, and OB=OC.

[0017] According to the present invention, a main shaft constant speed driven floating swashplate axial conical cylinder plunger pump is provided, wherein a plurality of cylinder holes are equally spaced along the circumference inside the cylinder body, the cylinder holes are inclined to the axis of the main shaft and communicate with the oil inlet, and a plurality of ball sockets are equally spaced along the circumference on the side of the rotary disk near the cylinder body, and the plunger is slidably connected in the cylinder hole, the ball head extending out of the cylinder hole and hinged to the ball socket.

[0018] According to the present invention, a main shaft constant speed driven floating swashplate axial conical cylinder plunger pump is provided, wherein the cylinder is a conical structure.

[0019] According to the present invention, a main shaft constant speed driven floating swashplate axial conical cylinder plunger pump is provided, wherein a channel is opened in the middle of the cylinder, a central spring is provided in the channel, the central spring is sleeved on the main shaft, and a plurality of push rods are provided on the cylinder along the axial direction, one end of the push rod passes through the cylinder and contacts the ball joint, and the other end of the push rod extends into the channel and is fixedly connected to the central spring.

[0020] According to the present invention, a main shaft constant speed driven floating swashplate axial conical cylinder plunger pump is provided, wherein a front end cover is fixedly connected to the front end of the pump body, a base is fixedly connected to the pump body, a bearing is fixedly connected between the front end cover and the base, the main shaft is rotatably connected to the pump body through the bearing, the swashplate is mounted on the base, a variable lever is installed in the pump body, and the swashplate is hinged to the variable lever.

[0021] According to the present invention, a constant speed driven floating swashplate axial conical cylinder piston pump is provided, wherein a pressure relief ring groove is provided on the side of the swashplate near the rotary disk, the rotary disk is located in the pressure relief ring groove, and a plurality of oil storage chambers are provided at equal intervals along the circumference on the side of the rotary disk near the swashplate, and an oil guide channel is provided in the oil storage chamber, the oil guide channel communicating with the ball socket;

[0022] The plunger has a channel, the cylinder bore is connected to the ball socket through the channel, and is configured such that when the oil in the cylinder bore enters the oil reservoir through the channel and the oil guide channel, the oil forms a static pressure support in the pressure relief ring groove.

[0023] Compared with the prior art, the present invention has the following advantages and technical effects:

[0024] This invention provides a main shaft constant velocity driven floating swashplate axial conical cylinder plunger pump. The main shaft is driven to rotate by an external prime mover. The rotary disc is connected to the main shaft through a hinge structure. When the main shaft rotates, it drives the rotary disc to rotate and gives it axial movement freedom, removing the axial movement restriction of the rotary disc at the hinge point. At the same time, the hinge structure improves the resistance to contact stress. By setting the inclined plunger to be inclined relative to the main shaft, the tail end is conical. The centrifugal force of the plunger generates a centrifugal force component along the axial direction of the plunger. Under the action of this centrifugal force component, it helps the plunger return movement when it is in the oil suction zone, further increasing the oil suction capacity of the pump. For axial plunger pumps of the same displacement, the conical cylinder structure has a lower PV value (i.e., the product of stress and linear velocity) and stronger oil suction capacity than the cylindrical cylinder structure. Therefore, the plunger pump with the conical cylinder structure can achieve a higher speed than the axial plunger pump with the cylindrical cylinder structure. This application reduces the restriction on the relative axial movement of the ball joint and the rotary table, improves the overall contact stress resistance of the pump, and can achieve higher speeds compared to axial piston pumps with cylindrical block structures. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0027] Figure 2 This is a quarter-section view of the overall structure of the present invention;

[0028] Figure 3 This is a quarter-section view of the hinge structure of the present invention;

[0029] Figure 4 This is a schematic diagram of the installation position of the hinge structure of the present invention;

[0030] Figure 5 This is a schematic diagram of the cylinder block structure of the present invention;

[0031] Figure 6 This is a schematic diagram of the rotary table structure of the present invention;

[0032] Figure 7 This is a comparison image of the rotary table before and after the swing of the present invention;

[0033] Figure 8 This is a schematic diagram of the ball joint structure of the present invention;

[0034] Figure 9 This is a schematic diagram of the cage structure of the present invention;

[0035] Figure 10 This is a schematic diagram of the distribution disk structure of the present invention;

[0036] Figure 11 This is a schematic diagram of the axis of the rotating structure of the present invention;

[0037] Figure 12 These are schematic diagrams of different cross-sections of the track of this invention;

[0038] Figure 13 This is a schematic diagram of the pressure relief ring groove structure of the present invention;

[0039] Figure 14 This is a schematic diagram of the oil storage chamber structure of the present invention;

[0040] The components are as follows: 1. Main spindle; 2. Variable displacement lever; 3. Front end cover; 4. Bearing; 5. Base; 6. Swashplate; 7. Rotary disc; 8. Cage; 9. Ball joint; 10. Ball; 11. Cylinder block; 12. Piston; 13. Distributor plate; 14. Turbine; 15. Push rod; 16. Center spring; 17. Cylinder bore; 18. Oil port; 19. Ball socket; 20. Outer raceway; 21. Inner raceway; 22. Through hole; 23. Distribution hole; 24. Pressure relief ring groove; 25. Oil reservoir; 26. Oil guide channel. Detailed Implementation

[0041] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0043] Reference Figures 1-14 This invention provides a main shaft constant velocity driven floating swashplate axial conical cylinder plunger pump, comprising: a pump body and a main shaft 1 installed within the pump body, the main shaft 1 being connected to an external prime mover.

[0044] A swash plate 6, a rotary table 7, and a cylinder 11 are sequentially arranged from the front end to the rear end of the pump body on the main shaft 1. The swash plate 6 is connected to the inner cavity of the pump body, and the rotary table 7 is adapted to the swash plate 6 and connected to several plungers 12 inside the cylinder 11.

[0045] A hinge structure is provided on the main shaft 1. The rotary disk 7 is connected to the main shaft 1 through the hinge structure and is configured such that the rotary disk 7 changes from spherical contact to linear contact through the hinge structure. When the main shaft 1 rotates, the rotary disk 7 and the hinge structure are allowed to have a degree of freedom to generate relative axial movement.

[0046] The plunger 12 inside the cylinder 11 is inclined along the axis of the main shaft 1.

[0047] In one embodiment of the present invention, the main shaft 1 is driven to rotate by an external prime mover, and the rotary disk 7 is connected to the main shaft 1 through a hinge structure. When the main shaft 1 rotates, it drives the rotary disk 7 to rotate and enables it to have the degree of freedom to move axially relative to the ball joint 9. This removes the limitation of the hinge point on the degree of freedom of the rotary disk to move axially relative to the ball joint in the prior art. Furthermore, by setting an inclined plunger 12, the tail end is made into a conical structure.

[0048] Specifically, for the same displacement, the diameter of the distributor plate 13 of the conical cylinder block 11 structure axial piston pump can be smaller than that of the cylindrical cylinder block structure axial piston pump. This is beneficial to improving the pump's oil suction capacity and reducing the PV value of the distributor pair. At the same time, since the piston 12 in the conical cylinder block 11 structure is arranged at an angle relative to the main shaft 1, the centrifugal force of the piston 12 will generate a centrifugal force component along the piston axial direction. Under the action of this centrifugal force component, it helps the piston 12 to return when it is in the oil suction zone, further increasing the pump's oil suction capacity. For axial piston pumps of the same displacement, the conical cylinder block 11 structure has a lower PV value and stronger oil suction capacity than the cylindrical cylinder block structure. Therefore, the speed of the conical cylinder block structure axial piston pump can reach a higher speed than that of the cylindrical cylinder block structure axial piston pump.

[0049] As an optional implementation, the hinge structure includes:

[0050] Ball joint 9 is mounted on spindle 1;

[0051] Cage 8 is fitted onto ball joint 9, and rotary table 7 is hinged to ball joint 9 via cage 8;

[0052] A number of balls 10 are rotatably connected to the cage 8 at equal intervals along the circumference, and the outer wall of the ball joint 9 and the inner wall of the rotary table 7 respectively contact the balls 10.

[0053] In one embodiment of the present invention, reference is made to Figure 3 The rotation between the rotary table 7 and the ball joint 9 is achieved by the set ball bearing 10, which enables it to have the function of relative axial movement.

[0054] As an optional implementation, the cage 8 has several through holes 22 at equal intervals along the circumference, the outer wall of the ball joint 9 has several inner raceways 21 at equal intervals along the circumference, and the inner wall of the turntable has several outer raceways 20 at equal intervals along the circumference. The several inner raceways 21 and the several outer raceways 20 correspond one-to-one with the several through holes 22, and the several balls 10 are respectively installed in the several through holes 22 and roll in the inner raceways 21 and the outer raceways 20.

[0055] In one embodiment of the present invention, reference is made to Figure 6 , Figure 7 , Figure 8 , Figure 9 When the central axes of the ball joint 9 and the rotary disk 7 form any angle between them, the centers of all the balls 10 are located on the bisecting plane of the angle between the central axes of the ball joint 9 and the rotary disk 7. Therefore, the ball joint 9 can drive the rotary disk 7 to rotate at a constant speed and synchronously. During the rotation, relative axial movement between the rotary disk 7 and the ball joint 9 is allowed to ensure the floating characteristics of the rotary disk 7. The cross section of the raceway is changed from a single circular arc raceway to an elliptical raceway and a double circular arc raceway. In the elliptical raceway, the line connecting the contact point of the ball 10 and the raceway and the center of the ball 10 forms a 45° angle with the radial direction of the center of the ball, which can achieve higher transmission efficiency and load-bearing capacity. In the double circular arc raceway, the contact angle between the ball 10 and the raceway can remain unchanged, so the transmission efficiency, load-bearing capacity and axial stiffness are relatively stable.

[0056] Specifically, the number of inner raceways 21 on the ball joint 9, outer raceways 20 on the rotary table 7, balls 10, and through holes 22 in the cage 8 is preferably 6, but other numbers may be used depending on the magnitude of the transmitted force and torque.

[0057] As an optional implementation, the through hole 22 is an oblong through hole, and the cross-section of the inner raceway 21 and the outer raceway 20 is one of a single circular arc, an ellipse or a double circular arc.

[0058] In one embodiment of the present invention, reference is made to Figure 12 The cross-sections of the inner raceway 21 and the outer raceway 20 are one of a single circular arc, an ellipse, or a double circular arc.

[0059] Specifically, the inner side of the rotary disk 7 is cylindrical rather than spherical, thus forming a linear contact with the outer spherical surface of the cage 8. The cage 8 is divided into inner and outer spherical surfaces, with the inner spherical surface engaging with the ball joint 9 and the outer spherical surface engaging with the cylindrical surface of the rotary disk 7. Relative axial movement can occur between the rotary disk 7 and the ball joint 9. The raceways on the rotary disk 7 and the ball joint 9 are straight grooves. After the two are assembled, the raceways formed by them contain balls 10, which are also installed in the holes of the cage 8. The cage 8 engages with the inner cylindrical surface of the rotary disk 7, thereby achieving axial movement.

[0060] As an optional implementation, the center of the outer spherical surface of the cage 8 is B, the center of the inner spherical surface of the cage 8 is C, and the point where the center of the plane formed by the swing center of the swashplate 6, the center of the cage 8, and the center of the ball head of the plunger 12 coincides is O, and OB=OC.

[0061] In one embodiment of the present invention, reference is made to Figure 7 , Figure 11 When the central axis of the cylinder block is at an angle to the axis of the main shaft 1, the straight groove raceway of the ball joint 9 of the main shaft 1 and the straight raceway of the rotary table 7 intersect at the angle bisector AA and pass through point O. At this time, the center C of the inner spherical surface of the cage 8 is in contact with the outer surface of the ball joint 9, and the center B of the outer spherical surface of the cage 8 always coincides with the central axis of the rotary table 7. That is, the cylindrical surface of the cage 8 and the rotary table 7 are in line contact, and OB = OC.

[0062] As an optional implementation, a plurality of cylinder holes 17 are equally spaced along the circumference inside the cylinder body 11. The cylinder holes 17 are inclined to the axis of the main shaft 1 and are connected to the oil inlet 18. A plurality of ball sockets 19 are equally spaced along the circumference on the side of the rotary table 7 near the cylinder body 11. The plunger 12 is slidably connected in the cylinder hole 17. The ball head extends out of the cylinder hole 17 and is hinged to the ball socket 19.

[0063] In one embodiment of the present invention, reference is made to Figure 4 The rotary table 7 is connected to the plunger 12 by hinge with the ball socket 19. Specifically, the plunger 12 is a thin rod plunger.

[0064] As an alternative implementation, the cylinder block 11 has a conical structure.

[0065] In one embodiment of the present invention, reference is made to Figure 5 The cylinder body 11 has a conical structure, which, together with the thin rod structure plunger 12, helps to reduce the distribution diameter of the distribution plate 13, thereby reducing the linear velocity of the cylinder body distribution surface and reducing the weight of the pump. Since the volume of the sealed working cavity formed in the cylinder bore 17 behind the plunger 12 is reduced, the hydraulic pressure of the oil in the cylinder bore 17 of the cylinder body 11 increases, forming high-pressure oil.

[0066] As an optional implementation, a channel is provided in the middle of the cylinder body 11, and a central spring 16 is provided in the channel. The central spring 16 is sleeved on the main shaft 1. Several push rods 15 are provided on the cylinder body 11 along the axial direction. One end of the push rod 15 passes through the cylinder body 11 and contacts the ball joint 9, and the other end of the push rod 15 extends into the channel and is fixedly connected to the central spring 16.

[0067] In one embodiment of the present invention, reference is made to Figure 4 A central spring 16 is provided in the channel. One end of the central spring 16 acts on the ball joint 9 through the push rod 15, causing the ball joint 9 to press against the rotary table 7, which in turn causes the rotary table 7 to press against the swashplate 6.

[0068] As an optional implementation, a front cover 3 is fixedly connected to the front end of the pump body, a base 5 is fixedly connected to the pump body, a bearing 4 is fixedly connected between the front cover 3 and the base 5, the main shaft 1 is rotatably connected to the pump body through the bearing 4, a swashplate 6 is mounted on the base 5, a variable lever 2 is installed in the pump body, and the swashplate 6 is hinged to the variable lever 2.

[0069] Specifically, the central axis of swashplate 6 forms an acute angle with respect to the straight line in the forward and backward direction.

[0070] In one embodiment of the present invention, reference is made to Figure 1 The pump body is also equipped with a variable lever 2, which is connected to the edge ball joint of the swashplate 6. Pushing the swashplate 6 to move the variable lever 2 will adjust the tilt angle of the swashplate 6.

[0071] As an optional implementation, a pressure relief ring groove 24 is provided on the side of the swash plate 6 near the rotary table 7, and the rotary table 7 is located in the pressure relief ring groove 24. A plurality of oil storage chambers 25 are provided at equal intervals along the circumference on the side of the rotary table 7 near the swash plate 6. Oil guide channels 26 are provided in the oil storage chambers 25, and the oil guide channels 26 are connected to the ball socket 19.

[0072] The plunger 12 has a channel, and the cylinder bore 17 is connected to the ball socket 19 through the channel. It is configured such that when the oil in the cylinder bore 17 enters the oil reservoir 25 through the channel and the oil guide channel 26, the oil forms a static pressure support in the pressure relief ring groove 24.

[0073] As an optional implementation, a distribution plate 13 is installed in the pump body, the distribution plate 13 is in contact with the cylinder body 11, and the distribution plate 13 is provided with a distribution hole 23.

[0074] In one embodiment of the present invention, reference is made to Figure 10 The distribution hole 23 is a waist-shaped hole, and the high-pressure oil is discharged through the oil discharge waist-shaped hole of the distribution plate 13.

[0075] Specifically, the other end of the central spring 16 acts on the cylinder 11, causing the cylinder 11 to press against the distributor plate 13.

[0076] Working principle of this invention:

[0077] The main shaft 1 is driven to rotate by the prime mover. The rotating main shaft 1 drives the cylinder 11 and the ball joint 9 to rotate synchronously through the spline connection. When the swashplate 6 is at 0 degrees, the balls 10 held in the through hole 22 of the cage 8 can roll freely on the center line of the inner raceway 21 on the ball joint 9 and the outer raceway 20 on the rotary table 7. The cage 8 ensures that the balls 10 are always on the same angle bisector. As the tilt angle of the swashplate 6 changes, that is, as the angle between the central axes of the rotary table 7 and the ball joint 9 changes, when the angle between the central axes of the rotary table 7 and the ball joint 9 is constant, the balls 10 held in the through hole 22 of the cage 8 are positioned by the cross action of the inner raceway 21 of the ball joint 9 and the outer raceway 20 on the rotary table 7. The ball joint 9 and the rotary table 7 transmit force and torque through the balls 10. The cage 8 has an inner spherical surface and an outer spherical surface. The inner spherical surface of the cage 8 is in contact with the spherical outer surface of the ball joint 9, and the outer spherical surface of the cage 8 is in contact with the cylindrical surface of the central through hole of the rotary disk 7. That is, the rotary disk 7 is supported on the ball joint 9 through contact. When the central axes of the ball joint 9 and the rotary disk 7 are at any angle, the centers of all the balls 10 are located on the bisecting plane of the angle between the central axes of the ball joint 9 and the rotary disk 7. Therefore, the ball joint 9 can drive the rotary disk 7 to rotate at a constant speed and synchronously. During the rotation, relative axial movement between the rotary disk 7 and the ball joint 9 is allowed, ensuring the floating characteristics of the rotary disk 7.

[0078] During the rotation cycle of cylinder 11, plunger 12 gradually extends outward from cylinder 11 under the action of rotary disk 7 and corresponding cylinder bore 17 in cylinder 11. As plunger 12 gradually extends, the volume of the sealed working chamber of cylinder bore 17 in cylinder 11 continuously increases, generating a partial vacuum. When cylinder bore 17, which forms a partial vacuum, rotates until oil port 18 aligns with distribution hole 23 of distribution plate 13, low-pressure oil from the hydraulic system is drawn into the cylinder bore 17 that forms a partial vacuum through distribution hole 23 of distribution plate 13.

[0079] As the cylinder body 11 continues to rotate, the plunger 12 is gradually pushed into the cylinder bore 17. This pushes out the oil that originally entered the cylinder bore 17. Furthermore, because the volume of the sealed working cavity formed behind the plunger 12 within the cylinder bore 17 decreases, the hydraulic pressure of the oil in the cylinder bore 17 increases, creating high-pressure oil. When the cylinder body 11 rotates until the oil inlet 18 aligns with the drain outlet of the distribution plate 13, the high-pressure oil is discharged through the drain outlet of the distribution plate 13.

[0080] This invention provides a main shaft constant speed driven floating swashplate axial conical cylinder plunger pump. The pump utilizes ball bearings 10 to achieve synchronous rotation between the rotary disk 7 and the ball joint 9, enabling relative axial movement. When the central axes of the ball joint 9 and the rotary disk 7 form any angle, the centers of all the ball bearings 10 lie on the bisector of the angle between their central axes. Therefore, the ball joint 9 can synchronously drive the rotary disk 7 at a constant speed, allowing relative axial movement between the rotary disk 7 and the ball joint 9 during rotation, ensuring the floating characteristics of the rotary disk 7. The raceway cross-section is modified from a single circular arc raceway to include an elliptical raceway and a double circular arc raceway. In the elliptical raceway, the line connecting the contact point of the ball bearing 10 and the raceway to the center of the ball bearing 10 forms a 45° angle radially through the center of the ball, achieving higher transmission efficiency and load-bearing capacity. In the double circular arc raceway, the contact angle between the ball bearing 10 and the raceway can... The transmission efficiency, load-bearing capacity, and axial stiffness remain unchanged, thus the transmission efficiency, load-bearing capacity, and axial stiffness are relatively stable. Since the plunger 12 in the conical cylinder block 11 structure is arranged at an inclination relative to the main shaft 1, the centrifugal force of the plunger 12 will generate a centrifugal force component along the axial direction of the plunger. Under the action of this centrifugal force component, it helps the return motion of the plunger 12 when it is in the oil suction zone, further increasing the oil suction capacity of the pump. In addition, under the same displacement, the diameter of the distribution plate 13 of the axial plunger pump with the conical cylinder block 11 structure can be made smaller than that of the distribution plate of the axial plunger pump with the cylindrical cylinder block structure. This is beneficial to improve the oil suction capacity of the pump and reduce the PV value of the distribution pair. For the same displacement axial plunger pump, the conical cylinder block 11 structure has a lower PV value and stronger oil suction capacity than the cylindrical cylinder block structure. Therefore, the speed of the axial plunger pump with the conical cylinder block structure can reach a higher speed than that of the axial plunger pump with the cylindrical cylinder block structure.

[0081] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0082] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A constant-speed driven floating swashplate axial conical cylinder piston pump, comprising: The pump body and the main shaft (1) installed in the pump body, the main shaft (1) being connected to an external prime mover, characterized in that: The main shaft (1) is provided with a swashplate (6), a rotary table (7) and a cylinder (11) in sequence from the front end of the pump body to the rear end of the pump body. The swashplate (6) is connected to the inner cavity of the pump body. The rotary table (7) is adapted to the swashplate (6) and connected to a number of plungers (12) in the cylinder (11). A hinge structure is provided on the main shaft (1). The rotary disk (7) is connected to the main shaft (1) through the hinge structure and is configured such that the rotary disk (7) changes from spherical contact to linear contact through the hinge structure. When the main shaft (1) rotates, axial movement can occur between the rotary disk (7) and the hinge structure. The plunger (12) inside the cylinder (11) is inclined along the axis of the main shaft (1); The hinge structure includes: a ball joint (9) disposed on the main shaft (1); a cage (8) sleeved on the ball joint (9), the rotary disk (7) being hinged to the ball joint (9) through the cage (8); a plurality of balls (10) rotatably connected to the cage (8) at equal intervals along the circumference, and the outer wall of the ball joint (9) and the inner wall of the rotary disk (7) respectively contacting the balls (10); a plurality of through holes (22) are equally spaced along the circumference on the cage (8), a plurality of inner raceways (21) are equally spaced along the circumference on the outer wall of the ball joint (9), and a plurality of outer raceways (20) are equally spaced along the circumference on the inner wall of the rotary disk (7), and a plurality of through holes (22) are equally spaced along the circumference on the inner wall of the rotary disk (7), and a plurality of through holes (22) are equally spaced along the circumference on the outer wall of the ball joint (9), and a plurality of outer raceways (20) are equally spaced along the circumference on the inner wall of the rotary disk (7), and a plurality of through holes (22) are equally spaced along the circumference on the outer wall of the ball joint (9), and a plurality of through holes (2 ... outer wall of the ball joint (9), and a plurality of through holes (22) are equally spaced along the circumference on the inner wall of the rotary The inner raceway (21) and the plurality of outer raceways (20) correspond one-to-one with the plurality of through holes (22). The plurality of balls (10) are respectively installed in the plurality of through holes (22) and roll in the inner raceway (21) and the outer raceway (20). The through hole (22) is a waist-shaped through hole. The cross-section of the inner raceway (21) and the outer raceway (20) is one of a single circular arc, an ellipse or a double circular arc. The center of the outer spherical surface of the cage (8) is B, the center of the inner spherical surface of the cage (8) is C, and the coincidence point of the center of the plane formed by the swing center of the swashplate (6), the center of the cage (8) and the center of the ball head of the plunger (12) is O, and OB = OC.

2. The spindle-driven floating swashplate axial conical cylinder plunger pump according to claim 1, characterized in that: The cylinder body (11) has a plurality of cylinder holes (17) evenly spaced along the circumference. The cylinder holes (17) are inclined to the axis of the main shaft (1) and are connected to the oil inlet (18). The rotary table (7) has a plurality of ball sockets (19) evenly spaced along the circumference on the side close to the cylinder body (11). The plunger (12) is slidably connected to the cylinder hole (17), with the ball head extending out of the cylinder hole (17) and hinged to the ball socket (19).

3. The spindle-driven, constant-speed floating swashplate axial conical cylinder plunger pump according to claim 1, characterized in that: The cylinder (11) has a conical structure.

4. The spindle-driven, constant-speed floating swashplate axial conical cylinder plunger pump according to claim 1, characterized in that: The cylinder body (11) has a channel in the middle, and a central spring (16) is installed in the channel. The central spring (16) is sleeved on the main shaft (1). Several push rods (15) are arranged axially on the cylinder body (11). One end of the push rod (15) passes through the cylinder body (11) and contacts the ball joint (9). The other end of the push rod (15) extends into the channel and is fixedly connected to the central spring (16).

5. A constant-speed driven floating swashplate axial conical cylinder plunger pump according to claim 1, characterized in that: A front cover (3) is fixedly connected to the front end of the pump body, a base (5) is fixedly connected to the pump body, a bearing (4) is fixedly connected between the front cover (3) and the base (5), the main shaft (1) is rotatably connected to the pump body through the bearing (4), the swashplate (6) is mounted on the base (5), a variable lever (2) is installed in the pump body, and the swashplate (6) is hinged to the variable lever (2).

6. A constant-speed driven floating swashplate axial conical cylinder plunger pump according to claim 2, characterized in that: The swash plate (6) has a pressure relief ring groove (24) on the side near the rotary table (7), the rotary table (7) is located in the pressure relief ring groove (24), and the rotary table (7) has a plurality of oil storage chambers (25) at equal intervals along the circumference on the side near the swash plate (6), and an oil guide channel (26) is provided in the oil storage chamber (25), the oil guide channel (26) is connected to the ball socket (19); The plunger (12) has a channel, the cylinder bore (17) is connected to the ball socket (19) through the channel, and is configured such that when the oil in the cylinder bore (17) enters the oil storage chamber (25) through the channel and the oil guide channel (26), the oil forms a static pressure support in the pressure relief ring groove (24).

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